[Mono-bugs] [Bug 79878][Maj] New - BeginConnect/EndConnect for Socket does not work correctly on connection error

bugzilla-daemon at bugzilla.ximian.com bugzilla-daemon at bugzilla.ximian.com
Thu Nov 9 11:43:48 EST 2006

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Changed by odie at cs.aau.dk.


--- shadow/79878	2006-11-09 11:43:48.000000000 -0500
+++ shadow/79878.tmp.9637	2006-11-09 11:43:48.000000000 -0500
@@ -0,0 +1,84 @@
+Bug#: 79878
+Product: Mono: Class Libraries
+Version: 1.1
+OS Details: 
+Status: NEW   
+Priority: Major
+Component: System
+AssignedTo: mono-bugs at ximian.com                            
+ReportedBy: odie at cs.aau.dk               
+QAContact: mono-bugs at ximian.com
+TargetMilestone: ---
+Summary: BeginConnect/EndConnect for Socket does not work correctly on connection error
+Description of Problem:
+When trying to connect a Socket instance asynchronously and the attempt
+fails for whatever reason, the connected bit is set true when it should be
+Steps to reproduce the problem:
+Run attached test case (tcp socket 1234 on localhost should be closed so
+the attempt to connect fails).
+Actual Results:
+socket.Connected is true when Callback is invoked, even though the
+connection failed, as the test case shows.
+Expected Results:
+When the callback registered with BeginConnect is invoked, Connected should
+be false if some error happened. Output for test case should thus be
+socket connected False, op completed True
+Hit key to end:
+How often does this happen? 
+Failure is 100% reproduceable on mono 1.1.something and current svn and
+work as expected on .Net.
+Additional Information:
+Comments to code snippets from mcs/class/System/System.Net.Socket/Socket.cs:
+(line 288-299)
+            public void Connect ()
+            {
+                try {
+                    if (!result.Sock.Blocking) {
+                        result.Sock.Poll (-1, SelectMode.SelectWrite);
+                        int success = (int)result.Sock.GetSocketOption
+(SocketOptionLevel.Socket, SocketOptionName.Error);
+                        if (success == 0) {
+                            result.Sock.connected = true;
+                        } else {
+                            result.Complete (new SocketException (success));
+                            return;
+                        }
+On instantiation of a Socket, connected is false. Connect calls Poll, which
+the snippet from below is from. I don't believe connected should be set
+true here, because the result of Poll_internal doesn't say whether the
+socket is connected or not that is reflected by GetSocketOption it seems
+from the code above.
+(line 1344-1358)
+            int error;
+            bool result = Poll_internal (socket, mode, time_us, out error);
+            if (error != 0)
+                throw new SocketException (error);
+            if (result == true) {
+                /* Update the connected state; for
+                 * non-blocking Connect()s this is
+                 * when we can find out that the
+                 * connect succeeded.
+                 */
+                connected = true;
+            }
+            return result;
+So from the point of solving my problem, removing connected = true; from
+Poll works (I tested it). If other relies on Poll setting connected I guess
+Poll could call GetSocketOption like Connect does.

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